what is the significance melville describes at the beginning of the chapter

"IT WAS A CLEAR STEEL-BLUE DAY. The firmaments of air and sea were hardly separable in that all-pervading azure; only, the pensive air was transparently pure and soft, with a woman’s look, and the robust and man-like sea heaved with long, strong, lingering swells, as Samson’s chest in his sleep."

The air and the blue of the sky were melded together with the blue of the rolling sea. The air is calm and beautiful like a woman...... the sea like a heaving, man of strength. This use of descriptive language allow the reader to see the separation of the is the picture of blue.... to see the horizon.